There are 4 definitions of os in English:

os1

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noun (plural ossa /ˈɒsə/)

Anatomy
A bone (used chiefly in Latin names of individual bones, e.g. os trapezium).
More example sentences
  • In this group, the cortex of the os sacrum was destroyed and had a spongelike rather than compact appearance.
  • Besides this unambiguous distinguishing character, a second, derived character, exists which is particular to the Carnivora: in the wrist the joint bones, scaphoid, lunate, and os centrale, are fused.

Origin

Latin.

Definition of os in:

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Word of the day hypnopompic
Pronunciation: ˌhɪpnə(ʊ)ˈpɒmpɪk
adjective
relating to the state immediately preceding waking up

There are 4 definitions of os in English:

os2

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noun (plural ora /ˈɔːrə/)

Anatomy
An opening or entrance to a passage, especially one at either end of the cervix of the womb.
More example sentences
  • The distance between the internal and external os was measured both as a straight line and also as a curved line along the endocervical canal.
  • The internal os closes by 3 days, the external os by 3 weeks.

Origin

mid 18th century: from Latin, 'mouth'.

Definition of os in:

There are 4 definitions of os in English:

Os3

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symbol

The chemical element osmium.

Definition of os in:

There are 4 definitions of os in English:

OS4

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Pronunciation: /əʊˈɛs
 
/

abbreviation

1(In calculating dates) Old Style.
1.1 Computing Open-source.
1.2 Computing Operating system.
1.3Ordinary Seaman.
1.4(In the UK) Ordnance Survey.
1.5(As a size of clothing) outsize.
1.6Out of stock.
1.7Overseas.

Definition of os in: